Method of making an automotive closure panel assembly

Abstract

A method may include providing an outer panel that may have a flange that defines at least one planar section. The flange may be heated at the at least one planar section, and the flange may be bent about the at least one planar section.

1. A method of hemming at least a portion of a panel assembly, the method comprising:
 providing an outer panel having a flange defining at least one planar section and having at least one first bend, and providing an inner panel having at least one second bend; 
 holding the inner panel adjacent the outer panel by a workpiece holder; 
 leaving the at least one planar section exposed out of the workpiece holder; 
 concentrating heat application to the at least one planar section to predefine a hem line across the at least one planar section; and 
 bending the at least one planar section at the predefined hem line, whereby the flange folds over the inner panel, wherein the predefined hem line and the at least one first bend are spaced away from each other via a portion of the at least one planar section, and wherein, after bending at the predefined hem line and folding the flange over the inner panel, the flange of the outer panel is folded over the at least one second bend of the inner panel. 
 
     
     
       2. A method as set forth in  claim 1  further comprising concentrating heat application away from the at least one first bend whereby the predefined hem line is more susceptible to bending than the at least one first bend. 
     
     
       3. A method as set forth in  claim 1  further comprising concentrating heat application away from the at least one first bend whereby the temperature at the at least one planar section is higher than the temperature at the at least one first bend. 
     
     
       4. A method as set forth in  claim 1  wherein bending the at least one planar section is performed without the use of a hard die radius. 
     
     
       5. A method as set forth in  claim 1  further comprising applying adhesive to adhere the inner panel and the outer panel together, and comprising concentrating heat application away from where the adhesive is applied. 
     
     
       6. A method as set forth in  claim 1  wherein concentrating heat application comprises aiming a laser at the at least one planar section to heat the at least one planar section to predefine a hem line across the at least one planar section. 
     
     
       7. A method as set forth in  claim 1  wherein concentrating heat application comprises using an induction coil to heat the at least one planar section to predefine a hem line across the at least one planar section. 
     
     
       8. A method as set forth in  claim 1  wherein the outer panel is composed of magnesium or a magnesium alloy. 
     
     
       9. A method of hemming at least a portion of an automotive closure panel assembly, the method comprising:
 providing a flange of an outer panel of an automotive closure panel assembly, the flange having at least one planar section; 
 providing the flange by forming at least one bend in the outer panel against a die that serves as a hard die radius; 
 heating the at least one planar section at a location away from the at least one bend; and 
 bending the flange about the heated location to form a second bend that is spaced away from the at least one bend by a portion of the at least one planar section, the second bend being formed without the use of a hard die radius. 
 
     
     
       10. A method as set forth in  claim 9  wherein heating comprises applying heat directly to the at least one planar section and not directly to the at least one bend. 
     
     
       11. A method as set forth in  claim 10  wherein applying heat comprises using a laser to apply heat directly to the at least one planar section. 
     
     
       12. A method as set forth in  claim 10  wherein applying heat comprises using an induction coil to apply heat directly to the at least one planar section. 
     
     
       13. A method as set forth in  claim 9  wherein bending comprises bending the flange about the heated location and not about the at least one bend. 
     
     
       14. A method as set forth in  claim 9  wherein providing comprises providing the flange being composed of magnesium or a magnesium alloy. 
     
     
       15. A method as set forth in  claim 9  further comprising providing an inner panel of the automotive closure panel assembly. 
     
     
       16. A method of hemming at least a portion of an automotive closure panel assembly, the method comprising:
 providing an inner panel and an outer panel of an automotive closure panel assembly, the outer panel being composed of magnesium or a magnesium alloy; 
 forming a flange in a periphery of the outer panel, the flange having at least one bend and at least one planar section; 
 holding the inner panel over the outer panel by a workpiece holder, with the flange being exposed out of the workpiece holder; 
 applying heat directly to the at least one planar section and away from the at least one bend to predefine a hem line along the at least one planar section, the predefined hem line being more susceptible to deformation than the at least one bend; and 
 bending the flange about the predefined hem line whereby the flange folds over the inner panel. 
 
     
     
       17. A method as set forth in  claim 16  wherein applying heat comprises using a laser. 
     
     
       18. A method as set forth in  claim 16  wherein applying heat comprises using an induction coil. 
     
     
       19. A method as set forth in  claim 16  wherein bending the flange comprises bending the flange about the predefined hem line and not about the at least one bend.